The general aim of this proposal is to develop and commercialize an innovative technology for gene expression profiling. This proprietary technology is based on direct amplification of RNA by RNA polymerase. Efficient protocols will be established for amplification and detection of RNA, mRNAs in particular, that will be suitable for in field applications. This novel technology should provide great improvements in both efficiency and ease of use as compared to the methods currently available, for example, RT-PCR. With the recent advances in RNA sample extraction and preservation as well as optical signal detection, this technology will also enable highly sensitive and high-throughput assessment of changes to gene expression in response to environmental exposure. Feasibility of this system will be first demonstrated in the proposed studies. Products will then be developed to provide easy-to- use, inexpensive and expedient tools for the identification of perturbations of gene expression patterns in response to toxic exposure. Alternative protocols will be exploited in order to establish the optimum techniques. The methodology may be formatted for microarray. This system is expected to have wide potential use for environmental studies and epidemiology surveys, as we as in other fields of biomedical research and development. PROPOSED COMMERCIAL APPLICATION: Detection methods, detection kits, and components of detection system developed by others.